Publications by authors named "David A Jansen"

Background: Topical nitrates have demonstrated efficacy in improving flap perfusion. However, evidence for nontopical nitrates in modulation of flap perfusion dynamics has yet to be consolidated. Here, we review evidence regarding the use of intravascular, sublingual, and oral nitrates in modulating flap perfusion.

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Biological aging is near-ubiquitous in the animal kingdom, but its timing and pace vary between individuals and over lifespans. Prospective, individual-based studies of wild animals-especially non-human primates-help identify the social and environmental drivers of this variation by indicating the conditions and exposure windows that affect aging processes. However, measuring individual biological age in wild primates is challenging because several of the most promising methods require invasive sampling.

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Low volumetric retention limits the utility of fat grafting. Although inclusion of stem cells and platelet-rich plasma have been proposed to enhance graft retention, accumulating evidence has failed to show a clear benefit. Here, we propose a strategy to pharmacologically enhance stemness of stem and progenitor cell populations in fat grafts to promote increased volume retention and tissue health.

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Background: Type 2 muscle flaps are characterized by major and minor pedicles, such that the minor pedicle is unreliable, and the major pedicle is a requirement for the success of the flap. The role of the minor pedicle, beyond the decreased caliber and decreased vascular territory in comparison to the major pedicle, is poorly understood. We sought to model the fluid dynamics of a model flap containing a major and minor pedicle to understand differences between the pedicles and the implications on perfusion.

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Background: Auricular composite grafts hold great potential for reconstructing the nasal soft tissue triangle with desired aesthetic results because there is ample tissue available for sufficient nasal ala projection and the natural curvature of the helical rim matches that of the alar rim. The use of auricular composite grafts also results in positive functional outcomes because of the cartilaginous airway support provided to widen the external nasal valve. Composite graft survival is highly dependent on graft size, as larger sized grafts have a higher metabolic demand.

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Background: Price transparency allows patients to estimate surgical procedure costs, which can affect where they elect to receive care and should theoretically result in hospitals setting lower and more uniform prices. To elucidate the traditionally opaque nature of health care pricing, the U.S.

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Background: The forehead flap is a local transposition flap based on a pedicled vessel commonly used to reconstruct facial defects. Often patients requiring reconstructions are smokers, yet the effects of smoking on forehead flaps are not well defined. Our study is aimed to examine smoking as a preoperative risk factor for complications following forehead flaps.

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Background: Inadequate wound closure is a feared complication following total knee arthroplasty (TKA). A knee with a multiple operative history, excessive scarring, and fibrosed surrounding soft tissue presents a significant challenge. In cases with preoperative uncertainty for sufficient soft tissue coverage because of ischemia and tension on closure, soft tissue expansion (STE) has been reported to be an effective tool for optimizing successful closure.

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Breast animation deformity is a known complication of subpectoral implant placement that is usually corrected by repositioning the implant to the prepectoral position. Other less common treatment options include performing the muscle splitting biplanar technique, triple plane technique, neuromodulator injections, and secondary neurotomies via transection of the pectoral muscle. We report a patient with animation deformity successfully treated with direct identification and ablation of the medial and lateral pectoral nerves using selective bipolar electrocautery.

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Surgical site infection after breast reconstruction is associated with increased length of hospital stay, readmission rates, cost, morbidity, and mortality. Identifying methods to reduce surgical site infection without the use of antibiotics may be beneficial at reducing antimicrobial resistance, reserving the use of antibiotics for more severe cases. Quaternary ammonium salts have previously been shown to be a safe and effective antimicrobial agent in the setting of in vitro and in vivo animal experiments.

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Background: Two-stage breast reconstruction with tissue expanders is one of the most common plastic surgery procedures. Acellular dermal matrix (ADM) has become popular for its ability to improve expansion parameters and aesthetics, albeit with a higher complication profile. We present data that support redefining 2-stage reconstruction to include tissue expanders regardless of final reconstructive modality to act as a bridge.

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Background: Membrane vesicles released by neoplastic cells into extracellular medium contain potential of carrying arrays of oncogenic molecules including proteins and microRNAs (miRNA). Extracellular (exosome-like) vesicles play a major role in cell-to-cell communication. Thus, the characterization of proteins and miRNAs of exosome-like vesicles is imperative in clarifying intercellular signaling as well as identifying disease markers.

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Background: All animals are anatomically constrained in the number of discrete call types they can produce. Recent studies suggest that by combining existing calls into meaningful sequences, animals can increase the information content of their vocal repertoire despite these constraints. Additionally, signalers can use vocal signatures or cues correlated to other individual traits or contexts to increase the information encoded in their vocalizations.

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Background: Craniosynostosis (CSS) results from the premature closure of one or more cranial sutures, leading to deformed calvaria at birth. It is a common finding in children with an incidence of one in 2000 births. Surgery is required in order to release the synostotic constraint and promote normal calvaria growth.

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Background: Soft-tissue fillers have become increasingly prominent in the practice of facial aesthetic medicine. The authors sought to evaluate the long-term clinical efficacy and safety of a calcium hydroxylapatite-based filler (Radiesse) for facial soft-tissue augmentation.

Methods: A total of 609 subjects received calcium hydroxylapatite injections in several facial areas: the nasolabial folds, marionette lines, oral commissure, cheeks, chin, lips, and radial lip lines.

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We present a case of a right external hemipelvectomy for chondroblastic osteosarcoma originating from the right ilium and reconstruction with salvage parts; cardiopulmonary bypass preserved anterior thigh free flap. The resection required sacrifice of the right common iliac artery and vein and the entire right gluteus maximus muscle. The first stage of the procedure was a high above-knee amputation on the ipsilateral leg.

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The stromal-vascular fraction of human adipose was subjected to in vitro adipogenesis on different extracellular matrix substrata. Adipose tissue was harvested from the breast of 25 to 45 year-old female patients undergoing elective surgery. After 24 d, less than 5% of stromal-vascular cells had converted to adipocytes on fibronectin, 13% to 28% on tissue culture plastic and collagen I; and 59% +/- 7% on Matrigel.

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Engineering autologous adipose constructs from cell culture is a promising strategy to overcome limitations of conventional soft-tissue implants. A methodology is presented to experimentally determine and mathematically model the differentiation kinetics of in vitro 3T3-L1 preadipocyte cultures that can aid in construct design. Relative rates of morphological and interfacial events during adipogenesis were compared.

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Some variation in breast size is normal and is common in most women. When this variation becomes large and appreciable asymmetry develops--greater than a one-cup size difference--the asymmetry often disrupts the patient's life. The etiology of most breast asymmetries is unknown; however, current theories on causes include endocrine, iatrogenic, and traumatic injury.

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